Human powered devices, most commonly bicycles, have migrated from a utilitarian purpose to a sport and recreation purpose over the course of the last 100 years.
The huge majority of bicycles sold and available in the marketplace today are pedal powered, driving a pair of cranks to which a chainring is connected that carries a chain that is operatively coupled to a toothed cog attached to a wheel, thereby transferring power to the wheel. Meanwhile the upper body is stabilised by providing the arms with a pair of handlebars located so the arms can be approximately perpendicular to the trunk of the body and able therefore to provide a leverage point and proper stability to the torso and the possibility to drive the hips when the rider is aiming to produce maximum power.
The nature of the handlebar is that is it positioned to provide stability to the torso while at the same time allowing the rider to steer the vehicle. On a standard safety bike or diamond frame bicycle the placement of the handlebars is such that the arms (or at least upper arms) are positioned somewhat parallel to the steering axis. This allows the bars to be pushed by one hand and pulled with the other hand while keeping the steering and balance of the bike under control. A rider sprinting to the finish line cants the frame left and right in time with her pedalling stroke and is enabled to do this by the particular structure and placement of the steering axis and handlebar system.
The mechanical solution of the handlebar and the cultural interpretation of its use is deeply embedded in cycling as a sport, the bicycle industry, and in the psychology of the general community in its attitudes to this mechanical object.
There is, however, one fundamental drawback to the handlebar that is acutely experienced by Time Trial (TT) riders who need to lower their upper body, narrow their elbows and point their forearms forward in an effort to reduce aerodynamic drag and allow greater speed with the same power output. On these bikes, a second pair of grips is often provided on a second pair of bars attached perpendicularly to the standard handlebar and at a spacing of approximately one hands width either side of the bicycle stem much closer together than the other provided pair of bars. Collectively handlebars including two pairs of bars, one inboard of the other pair, are often referred to as one or both of time trail bars and triathlon bars. To the rear end of these additional inboard bars are often mounted a pair of shaped pads that support the forearm close to the elbow. The drawback of this arrangement is that the bike carries two sets of grips, so at all times the superfluous pair of grips and their supporting framework is creating aerodynamic drag and adding weight thereby requiring power from the rider's limited supply and thus preventing the rider from achieving their best or fastest time.
Triathlon bars typically place thumb shift levers on the ends of the inboard bars as a user is likely going to be resting his hands on these bars most often during a time trail or a triathlon preventing the need for the user to move his or her hands and disrupt aerodynamic flow to change gears. The brakes are not used nearly as often during a time trial and as such the brake levers are most often placed on the outboard pair of bars at their respective distal ends. While moving a user's arms from the inboard to outboard position will induce drag that will use energy, the amount lost will be much less than the kinetic energy the user is intending to lose through the application of the brakes anyhow.
Problems can arise when the user is on one set of the bars and desires to effect a change requiring one or both of his/her hands to be on the other set of bars. For instance, while climbing and using the outer bars for leverage, the user must reach in to the inner bars to change the gear which can have a deleterious effect on momentum especially when the user is using the bars as a leverage point to assist in propulsion.
More significantly, if the rider is crouched low on the inner bars and is at speed when a dangerous road hazard is identified, there is a critical delay while the rider moves their hand to the outer bars in order to apply the brakes. The European standard for bicycle braking performance is consistent with a de-acceleration at half the acceleration due to gravity, or in simple numbers, 5 meters per second squared (5 m/s2). Road safety studies and simple calculations of the distance travelled at 46.8 kph, or 13 m/s during the time it takes to apply the brakes shows how critical reaction time is. At 46.8 kph or 13 m/s, a speed that is easily attained on a time trial bicycle, the braking distance is 16.9 m.
A study titled ‘Evaluation of brake reaction times on a motorcycle’ was produced by the Promocycle Foundation in Quebec, Canada in Jan. 5, 2003 (FMQ-BRT 0.154). This study shows that if the hand is positioned over the front brake lever an average reaction time of 0.359 seconds was recorded, while if the hand was not covering the lever, an average braking reaction time of 0.545 was found, a difference of 0.186 seconds—it takes valuable time to lift the right fingers or right foot over the brake levers of a motorcycle. At 13 m/s, a rider will travel 2.4 m during the reaction time, so the total stopping distance is unlikely to be less than 19.3 m.
There are no studies known to the inventor on the braking reaction time taken by a time trial rider if the body is in the aero position with hands on the inner grips or the inboard bars while the brake levers are on the outer bars. We can note that having the right hand fingers over the front brake lever of a motorcycle is a very close analogue for having the fingers of either or both hands over the brake levers on a bicycle. We can note the 0.186 second improved time if the rider covers the lever with the fingers rather than wrap the fingers on the handlebar, so we know that even very small preparatory movements cost valuable time. It is conservative to expect that a time trial rider will take at least one second to use her back muscles to lift her upper body weight and allow her hands to transfer to the outer grips whereupon the brake levers can be actuated. For the purposes of illustration, we can calculate the stopping distance when one second is added to the reaction time caused by the rider moving their hands to the outer grip position in order to apply the brakes.
A further one second delay to begin applying the brakes causes the rider to overshoot the possible stopping distance by 13 meters, if the rider is travelling at 13 m/s. This distance of 13 m is not far short of the total stopping distance of a rider who is ready to apply the brakes, 19.3 m. At the stopping point achieved by a rider at 13 m/s braking at 0.5 g with a normal reaction time, a similar rider with a reaction time delayed by one seconds will be still travelling 11.4 m/s or 41 kph, fast enough to do serious injury to the rider in a situation where a bicycle without this fundamental flaw would have pulled up safely. This is fundamentally dangerous.
To address this fundamental danger to the time trial rider, especially when time trial bikes are ridden in traffic rather than on controlled courses, it is possible to install a second brake lever pair to the inner bars.
Folding handlebars that permit a user to fold a bicycle for transport or storage are known in the prior art; however, the prior art does not disclose handlebars that can be moved from an outer position to a more aerodynamic position. The prior art further fails to disclose or suggest handlebars in which the movement of the bars can be accomplished while the bicycle is being ridden.